multiple ports: Update MAINTAINER

Change udvzsolt@gmail.com to uzsolt@uzsolt.hu on all relevant ports:
audio/musicpc
databases/adminer
deskutils/fet
graphics/mupdf
graphics/timg
graphics/zathura-pdf-mupdf
sysutils/rdiff-backup
textproc/urlview
www/kohana
x11/dzen2
x11-wm/herbstluftwm

PR: 220323
Submitted by: Zsolt Udvari <uzsolt@uzsolt.hu> (maintainer)
Approved by: mat (co-mentor)
Differential Revision: https://reviews.freebsd.org/D11469